package ll.leon.com.widget_animation_effect.helper;

import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;

import java.util.Random;    
    
/**  
 * Created by yao  
 * 用于图片验证码的工具类  
 */    
public class CodeUtils {    
    private static final char[] CHARS = {    
            '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',    
            'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',    
            'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',    
            'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',    
            'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'    
    };    
    
    private static CodeUtils mCodeUtils;    
    private int mPaddingLeft, mPaddingTop;    
    private StringBuilder mBuilder = new StringBuilder();    
    private Random mRandom = new Random();    
    
    //Default Settings    
    private static final int DEFAULT_CODE_LENGTH = 6;//验证码的长度  这里是6位    
    private static final int DEFAULT_FONT_SIZE = 60;//字体大小    
    private static final int DEFAULT_LINE_NUMBER = 3;//多少条干扰线    
    private static final int BASE_PADDING_LEFT = 20; //左边距    
    private static final int RANGE_PADDING_LEFT = 30;//左边距范围值    
    private static final int BASE_PADDING_TOP = 70;//上边距    
    private static final int RANGE_PADDING_TOP = 15;//上边距范围值    
    private static final int DEFAULT_WIDTH = 300;//默认宽度.图片的总宽    
    private static final int DEFAULT_HEIGHT = 100;//默认高度.图片的总高    
    private static final int DEFAULT_COLOR = 0xDF;//默认背景颜色值    
  
    private String code;  
    
    public static CodeUtils getInstance() {    
        if(mCodeUtils == null) {    
            mCodeUtils = new CodeUtils();    
        }    
        return mCodeUtils;    
    }    
    
    //生成验证码图片    
    public Bitmap createBitmap() {    
        mPaddingLeft = 0; //每次生成验证码图片时初始化    
        mPaddingTop = 0;    
    
        Bitmap bitmap = Bitmap.createBitmap(DEFAULT_WIDTH, DEFAULT_HEIGHT, Config.ARGB_8888);    
        Canvas canvas = new Canvas(bitmap);    
    
        code = createCode();    
    
        canvas.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR));    
        Paint paint = new Paint();    
        paint.setTextSize(DEFAULT_FONT_SIZE);    
    
        for (int i = 0; i < code.length(); i++) {    
            randomTextStyle(paint);    
            randomPadding();    
            canvas.drawText(code.charAt(i) + "" , mPaddingLeft, mPaddingTop, paint);    
        }    
    
        //干扰线    
        for (int i = 0; i < DEFAULT_LINE_NUMBER; i++) {    
            drawLine(canvas, paint);    
        }    
    
        canvas.save(Canvas.ALL_SAVE_FLAG);//保存    
        canvas.restore();    
        return bitmap;    
    }    
    /** 
     * 得到图片中的验证码字符串 
     * @return  
     */  
    public String getCode() {  
        return code;  
    }  
    
    //生成验证码    
    public String createCode() {    
        mBuilder.delete(0, mBuilder.length()); //使用之前首先清空内容    
    
        for (int i = 0; i < DEFAULT_CODE_LENGTH; i++) {    
            mBuilder.append(CHARS[mRandom.nextInt(CHARS.length)]);    
        }    
    
        return mBuilder.toString();    
    }    
    
    //生成干扰线    
    private void drawLine(Canvas canvas, Paint paint) {    
        int color = randomColor();    
        int startX = mRandom.nextInt(DEFAULT_WIDTH);    
        int startY = mRandom.nextInt(DEFAULT_HEIGHT);    
        int stopX = mRandom.nextInt(DEFAULT_WIDTH);    
        int stopY = mRandom.nextInt(DEFAULT_HEIGHT);    
        paint.setStrokeWidth(1);    
        paint.setColor(color);    
        canvas.drawLine(startX, startY, stopX, stopY, paint);    
    }    
    
    //随机颜色    
    private int randomColor() {    
        mBuilder.delete(0, mBuilder.length()); //使用之前首先清空内容    
    
        String haxString;    
        for (int i = 0; i < 3; i++) {    
            haxString = Integer.toHexString(mRandom.nextInt(0xFF));    
            if (haxString.length() == 1) {    
                haxString = "0" + haxString;    
            }    
    
            mBuilder.append(haxString);    
        }    
    
        return Color.parseColor("#" + mBuilder.toString());    
    }    
    
    //随机文本样式    
    private void randomTextStyle(Paint paint) {    
        int color = randomColor();    
        paint.setColor(color);    
        paint.setFakeBoldText(mRandom.nextBoolean());  //true为粗体，false为非粗体    
        float skewX = mRandom.nextInt(11) / 10;    
        skewX = mRandom.nextBoolean() ? skewX : -skewX;    
        paint.setTextSkewX(skewX); //float类型参数，负数表示右斜，整数左斜    
//        paint.setUnderlineText(true); //true为下划线，false为非下划线    
//        paint.setStrikeThruText(true); //true为删除线，false为非删除线    
    }    
    
    //随机间距    
    private void randomPadding() {    
        mPaddingLeft += BASE_PADDING_LEFT + mRandom.nextInt(RANGE_PADDING_LEFT);    
        mPaddingTop = BASE_PADDING_TOP + mRandom.nextInt(RANGE_PADDING_TOP);    
    }    
}    